Becasina Gigante/Giant Snipe/Gallinago undulata

Nombre en español: Becasina Gigante

Nombre en ingles: Giant Snipe

Nombre científico: Gallinago undulata

Familia: Scolopacidae

Canto: Jeremy Minns

La becasina gigante (Argentina, Paraguay, Colombia, Venezuela, Uruguay) o agachadiza gigante (Gallinago undulata), es una especie de ave caradriforme perteneciente al género Gallinago que integra la familia Scolopacidae. Es nativa de América del Sur.Gallinago undulata gigantea; ilustración de Huet le Jeune y Prêtre, 1838.

Es la Caica más grande en Colombia y la única con primarias barradas. Su nombre Gallinago significa similar a una gallina y deriva de las raíces latinas gallina = gallina y ago = similar a. Su epíteto undulata deriva del latín y significa con marcas en forma de onda.

Distribución y hábitat

Se distribuye separadamente en Colombia, Venezuela, Guyana, Surinam, Guayana Francesa y el extremo nordeste de Brasil y al sur se encuentra en Bolivia, Paraguay, sureste de Brasil y probablemente también en Uruguay y nordeste de Argentina.
Habita en pastos altos en pantanos, pastizales inundados, a veces en pastizales más secos, esteros en sabanas.

En Colombia puntualmente se encuentra en la vertiente oriental de la cordillera Occidental en el extremo sur del departamento de Antioquia a 1500 m de altura sobre el nivel del mar. También al oriente de los Andes en los departamentos del Meta y Vaupés.

Descripción

Es la especie mayor de su género y alcanza entre 40 y 43,5 cm de longitud. Tiene un cuerpo robusto y patas relativamente cortas para un ave zancuda. Tiene amplias alas redondeadas y un pico recto muy largo: el pico de G. u. gigantea alcanza hasta 12.0 cm de largo, en tanto el de G. u. undulata llega hasta 11,5 cm. Su dorso, cabeza y cuello son rayados y estampados con bordes negro, marrón y castaño, con las plumas formando líneas distintas en su espalda. El vientre es blanco con barras castañas en los flancos. Las plumas de vuelo están bloqueadas, una característica única de esta coica. Las patas son de color verde grisáceo. No se han observado diferencias de plumaje relacionada con la edad o el sexo.

Comportamiento

Llega a algunas áreas después de las lluvias, pero su movilidad estaciona aún no ha sido bien estudiada.
Rara vez se ve posar sobre el suelo seco y su hábitat preferido son las áreas inundadas, en las que generalmente está solitaria. Su hábito de alimentación nocturna hace más difícil estudiar su comportamiento. Se sabe queu dieta incluye las ranas. En Brasil se han encontrado nidos con huevos en septiembre y de noviembre a principios de enero; son colocados en elevaciones entre los pantanos y la hembra pone allí 2 a 4.

Hace una llamada kek-kek cuando avanza en las áreas inundadas y otra llamada, áspera trisilábica cuando realiza su vuelo de visualización nocturna. Otras coicas hacen una exhibición aérea, volando alto en círculos, descienden con fuerza y se oye un tamborileo, causado por las vibraciones al modificar las plumas externas de la cola. Aunque en esta especie se sabe de vuelos nocturnos, aún no se consigue registrar el tamborileo.

Sistemática

Descripción original

La especie G. undulata fue descrita por primera vez por el naturalista neerlandés Pieter Boddaert en 1783 bajo el nombre científico Scolopax undulata; localidad tipo «Cayenne».

Taxonomía

El género se llamaba anteriormente Capella, y este nombre era erróneamente considerado como antecediento a Gallinago. Algunos autores sugieren que la subespecie gigantea merecería tratamiento como especie separada.

Subespecies

Según la clasificación del Congreso Ornitológico Internacional (IOC) (Versión 4.4, 2014) y Clements Checlist 6.9, se reconocen 2 subespecies, con su correspondiente distribución geográfica:

Gallinago undulata undulata (Boddaert, 1783) – oeste y este de Colombia; Venezuela al extremo norte de Brasil y probablemente hacia el este hasta las Guayanas.
Gallinago undulata gigantea (Temminck, 1826) – este de Bolivia, Paraguay y sureste de Brasil; probablemente también en Uruguay y noreste de Argentina.

Solo la subespecie nominal se encuentra en Colombia.

Giant snipe

The giant snipe (Gallinago undulata) is a stocky wader. It breeds in South America. The nominate subspecies G. u. undulata occurs in two distinct areas, one in Colombia, and the other from Venezuela through Guyana, Suriname and French Guiana to extreme north-eastern Brazil. The southern subspecies G. u. gigantea is found in eastern Bolivia, eastern Paraguay and south-east Brazil, and probably also in Uruguay and north-eastern Argentina.

It occurs in tall vegetation in swamps and flooded grasslands, and occasionally in dry savannah. It ranges from the lowlands up to 2,200 m altitude.

It seems to arrive in some areas after rain, but its seasonal movements are very poorly understood.

Taxonomy

The giant snipe was described by the French polymath Georges-Louis Leclerc, Comte de Buffon in 1780 in his Histoire Naturelle des Oiseaux from a specimen collected in Cayenne, French Guiana. The bird was also illustrated in a hand-coloured plate engraved by François-Nicolas Martinet in the Planches Enluminées D’Histoire Naturelle which was produced under the supervision of Edme-Louis Daubenton to accompany Buffon’s text. Neither the plate caption nor Buffon’s description included a scientific name but in 1783 the Dutch naturalist Pieter Boddaert coined the binomial name Scolopax undulata in his catalogue of the Planches Enluminées. The giant snipe is now placed in the genus Gallinago that was introduced by the French zoologist Mathurin Jacques Brisson in 1760. The generic name is New Latin for a woodcock or snipe from Latin gallina, «hen» and the suffix -ago, «resembling». The specific epithet undulatus is Latin for «with wave-like markings».

Two subspecies are recognised:

G. u. undulata (Boddaert, 1783) – Colombia, Venezuela, the Guianas, north Brazil
G. u. gigantea (Temminck, 1826) – east Bolivia to Paraguay, southeast Brazil and northeast Argentina

Description

This is the largest snipe at 40–43.5 cm in length. G. u. gigantea, as its name suggests, is larger than the nominate subspecies with little overlap in size; for example, its bill length is usually more than 12.0 cm, whereas G. u. undulata is usually less than 11.5 cm.

The giant snipe has a stocky body and relatively short legs for a wader. It has broad rounded wings like a woodcock and a very long bill. Its upperparts, head and neck are streaked and patterned with black and brown, and chestnut edges to the feathers form distinct lines down its back. The belly is white with brown barring on the flanks. The flight feathers are barred, a feature unique to this snipe. The horn-coloured bill is very long and straight. The legs and feet are greyish-green.

No plumage differences related to age or sex are known, but in other snipe the sexes are similar and immature birds differ only in showing pale fringes on the wing coverts.

The giant snipe has a kek-kek call when flushed, and a rasping trisyllabic call is given in its nocturnal display flight.

Giant snipe can be distinguished from the sympatric common and the Magellan snipe by its huge size and rounded wings. The other large species, Andean, Fuegian and imperial snipe, are upland species which lack the well-defined upperpart markings and white belly shown by giant snipe. The noble snipe is more similar to giant, but obviously smaller-bodied.

Behaviour

Nests of the southern race have been found in Brazil in September and from November to early January. They are placed on a hillock between swamps, and 2–4 eggs are laid. No nests of the nominate subspecies have been found.

This species is rarely seen on the ground, and its habitat, reluctance to flush until almost trodden on, cryptic plumage, and nocturnal feeding mean its habits are almost unknown. Its diet apparently includes frogs. The giant snipe is usually seen alone when flushed.

Other Gallinago snipes have an aerial display, which involves flying high in circles, followed by a powerful stoop during which the bird makes a drumming sound, caused by vibrations of modified outer tail feathers. This species displays at night, but it is not known whether it drums.

Status

The giant snipe is hunted through most of its range, its large size making it easier to shoot than other snipes. Habitat loss is also a threat, at least in part of its range. It is nowhere common, and is local and uncommon in Colombia and Venezuela, but its nocturnal habits and extremely secretive behaviour might exaggerate its apparent scarcity, and it is currently not thought to be threatened.

Given its crepuscular and nocturnal habits that the Giant Snipe is a relatively poorly known and infrequently observed species is unsurprising. The species’ range is wide, but apparently highly fragmented, in the north being found over parts of northern Colombia, Venezuela, northernmost Brazil and the Guianas, while in the south a separate subspecies occurs in eastern Bolivia, Paraguay and over much of southern Brazil, albeit locally. Throughout, the species inhabits tall, swampy vegetation, wet pastures, and flooded grasslands, at elevations up to at least 2200 m. As befits its name, the Giant Snipe is the largest of its genus, and has a very long, deep-based bill; plumage, however, is broadly typical of all Gallinago. The Giant Snipe is usually encountered alone, but is most likely to be detected by either a chance ‘flushing’, or by listening for the species’ display-flight calls in a suitable locality at nightfall.